The aim of the study was to investigate the effects of high-fat diets before pregnancy and/or during pregnancy on fetal development.Main methods:
Female mice were fed with standard diets (SD) or high-fat diets (HFD). After 12weeks, females were mated. In the SD+SD and HFD+SD groups, pregnant mice were fed with standard diets. In the SD+HFD and HFD+HFD groups, pregnant mice were fed with high-fat diets. All pregnant mice were sacrificed on gestational day (GD) 16.Key findings:
Fetal weight and crown-rump length were increased in SD+HFD-fed mice, whereas were decreased in HFD+SD-fed mice. The levels of CRP and TNF-α in maternal serum and amniotic fluid were elevated in all HFD-fed mice. Placenta weight was elevated in SD+HFD-fed but not in HFD+SD-fed mice. Blood sinusoid areas, and the number of Ki67-positive cells, a marker of cell proliferation, were elevated in placental labyrinth layer of SD+HFD-fed mice, but decreased in HFD+SD-fed mice. Finally, placental Fatp1, a fatty acid transporter gene, was up-regulated in SD+HFD-fed mice. By contrary, placental Fatp1, and Snat2, an amino acid transporter, were down-regulated in HFD+SD-fed mice. Moreover, the levels of placental FATP4 and SNAT2 were up-regulated in SD+HFD-fed mice.Significance:
HFD before pregnancy and HFD during pregnancy differentially disturb fetal growth development. HFD before pregnancy-induced fetal SGA might be partially attributed to inflammatory cytokines and mediators derived from maternal adipose tissue. By contrary, HFD during pregnancy-induced fetal overweight may be partially attributed to the increase of placental nutrient transport capacity.